When a current strongbox lockset is mounted, a door of a strongbox needs to be provided with a through hole for a connection line or a transmission shaft to pass through. If an input unit outside the door of the strongbox is removed, a thin rod can strike the lockset or a lock case after passing through the through hole on the door of the strongbox, such that a relatively weak portion of the lockset is knocked off. In this way, the lockset is possibly opened technically.
Most existing locksets have such a problem that if a lockset is struck from the outside of a door of the strongbox, both a dial and a cover plate inside the lockset may be knocked off, resulting in a hidden danger of technical unlocking.